Billet grinder



Dec. 13, 1955 w. K. LOWE BILLET GRINDER l0 Sheets-Sheet 1 Filed April 1,1952 ENTOR. VI ZILLACEKLOWE.

A TTOKNEYS.

Dec. 13., 1955 w. K. LOWE 2,72

BILLET GRINDER Filed April 1, 1952 10 Sheets-Sheet 2 IN VEN TOR.

MLLACEKLOWE.

Dec. 13, 1955 w. K. LOWE 2,726,490

BILLET GRINDER Filed April 1, 1952 10 Sheets-Sheet 3 w. K. LOWE BILLETGRINDER Dec. 13, 1955 10 Sheets-Sheet 4 Filed April 1, 1952 INVENTOR.

MLLAcE Lot V5 BY ATTORNEYS.

Dec. 13, 1955 w. K. LOWE BILLET GRINDER l0 Sheets-Sheet 5 Filed April 1,1952 INVENTOR. VVALLA CEKLO WE.

WM 8 W ATTORNEYF.

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1 I I l L I i I i I I J Filed April 1, 1952 Dec. 13, 1955 w. K. LOWE2,726,490

BILLET GRINDER Filed April 1, 1952 10 Sheets-Sheet '7 AIR REGULATOR- 140Flu-ER LUBE/CATO)? 0 0 SAFETY ADELE/95E 44 CYLINDEE 5oz. ENOIDCONTROLLED VA (.vES

5114.57- TURNER 81 CLAMP/N6 CYLINDERS 8Q 007' OPERA TED INVENTOR. MLLACEKLOWE.

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Filed April 1, 1952 10 Sheets-Sheet 8 INVENTOR.

VI/ALLACE [flow/E. WMKM Dec. 13, 1955 w. K. LOWE 2,726,490

BILLET GRINDER Filed April 1, 1952 '10 Sheets-Sheet 1o INVENTOR. M ALL/ICE KLOWE United States Patent BILLET GRINDER Wallace K. Lowe, Syracuse,N. Y., assiguor to Crucible Steel Company of America, New York, N. Y., acorporation of New Jersey Application April 1, 1952, Serial No. 279,739

24 Claims. (Cl. 51-45) This invention relates to apparatus forautomatically grinding surfaces of metal billets such as, for example,rolled or forged steel billets.

This application is a continuation-in-part of my copending applicationSerial No. 253,242, filed October 26, 1951 and entitled Billet Grinder.

Rolled or forged steel billets have, in an intermediate stage in theirmanufacture, relatively rough and uneven surfaces as a result of arolling, hammer-forging or cogging operation, and for removingdecarburized surface and minor surface imperfections, such asirregularities, slivers and small cracks and for providing a relativelysmooth surface, free from imperfections, for subsequent rolling andforging operations, it has been the practice to surface grind thesebillets by manual or automatic grinding apparatus employing an abrasivegrinding wheel which traverses the imperfect surfaces of the billets. Inknown types of manual and automatically controlled grinding apparatus ofthis type the grinding pressure has been controlled either manually orthe pressure has been maintained constant irrespective of the load onthe grinding wheel and hence the load on the motor or other deviceemployed for driving the grinding wheel. Such arrangements areunsatisfactory not only because they produce uneven grinding, but alsobecause a constant pressure on the grinding wheel may cause the grindingwheel to cut the surface of the billet either too rapidly or too slowly.This is particularly true when the characteristics of the surface of thebillet vary across the face of the billet.

Also, in known types of automatic or semi-automatic billet grindingapparatus it has been customary to move the grinding wheel rapidlytransversely across the surface of the billet as the billet is movedslowly in the direction of the longitudinal axis of the billet. It hasbeen found that with this relationship between the movement of thebillet and the grinding wheel, relatively high temperatures develop atthe point of contact of the wheel with the billet because there is arelatively short period of time between the time that the grinding wheelcontacts one spot on the billet and the next adjacent spot on thesurface of the billet. This produces overheating of the billet withresulting surface decarburization, etc.

Furthermore, in connection with known types of automatic machines themechanism which is reciprocated with the grinding wheel has beenrelatively heavy and complicated both because it was necessary toreciprocate the grinding wheel at a rapid rate and because of theequipment heretofore employed for forcing the grinding wheel against abillet.

It is an object of the present invention to provide an automaticgrinding machine which does not have the disadvantages mentioned aboveand which is simple and economical to manufacture and operate.

In accordance with the preferred embodiment of the present invention, apivotally mounted beam is provided which has a grinding wheel and itsdriving motor mounted on one side of the pivot point thereof. Acounter-Weight whose position is adjustable along the length of the beamis provided on the opposite side of the pivot point and the position ofthe counter-weight along the length of the beam is controlled by theenergy consumed by the motor and hence by the motor load. The motor loadis, of course, proportional to the load on the grinding wheel andtherefore is related to the rate at which material is removed from thesurface of the billet. As the load on the wheel, and hence on the motor,increases due to changes in the characteristics of the surface of thebillet, the counter-weight is moved away from the pivot point and thepressure on the grinding wheel is decreased to compensate for thechanges in surface characteristics. Conversely, as the load on the wheeltends to decrease, the counter-weight is moved toward the pivot point sothat the pressure on the Wheel is increased. Thus, the pressure of thegrinding wheel against the billet is not constant but, instead, it isvariable so that the load on the grinding wheel is maintained at asubstantially constant value.

Also, in the preferred embodiment of the invention, the billet to beground is mounted on a table which moves back and forth rapidly along apath which is parallel to the longitudinal axis of the billet. At thesame time, the grinding wheel is moved slowly in a direction transverseto the longitudinal axis of the billet. Thus, over the major portion ofthe surface of a billet there is a relatively longer period of timebetween the times that the grinding wheel is operating on a firstsurface and then on an adjacent surface, and a greater area on thebillet is ground between each reversal of the table than when thegrinding wheel is moved back and forth rapidly and the table is movedslowly.

Because the grinding wheel moves transversely of the longitudinal axisof the billet at a comparatively slow rate and because of thearrangement provided for the control of the load on the grinding wheel,it is possible to mount only a relatively small number of parts on thepivoted beam and to provide relatively small and simple apparatus forreciprocating the beam. Accordingly, a further feature of my inventionis the simplicity of the structure and the apparatus required forreciprocating the grinding wheel.

In accordance with a further feature of my invention, I provide controlsfor producing a sehort stroke reciprocation of the billet-carrying tableat any position of the grinding wheel on the surface of the billet. Thisfeature is provided to permit extra grinding of portions of the billetsurface which require such grinding without hand operation of thegrinding wheel and without traversing the entire length of the billet.

Also, I provide a pair of pivotally and slidably mounted clamping armsfor clamping the billet at both its ends and one side. The clamping armsare operated by a pair of fluid actuated cylinder and piston means whichalso set the positions of the table reciprocation controls and hence thelength of table reciprocation stroke is controlled in accordance withthe length of a billet being ground.

In addition to the above features, the preferred embodiment of myinvention includes a quick-acting, air actuated cylinder and pistonmeans for lifting the grinding wheel in the event that it passes beyondthe end of a billet and controls for reducing the pressure of thegrinding wheel on the billet as it approaches the corners thereof toprevent thereby undesirable rounding of the corners.

Other objects and advantages of the invention will more fully appearfrom the following detailed description setting forth the manner inwhich I now prefer to practice the invention and from the accompanyingdrawings in which:

Fig. 1 is a side elevation view of the preferred embodiment of myinvention; I

Fig. 2 is a plan view of the embodiment shown in Fig. 1;

Fig. 3 is a front elevation view of the preferred embodiment of theinvention shown in Figs. 1 and 2;

Fig. 4 is a side elevation view of the embodiment shown in the precedingfigures taken from the opposite side from the view in Fig. 1;

Fig. 5 is a fragmentary, plan view of the embodiment of the precedingfigures and shows the billet table clamping devices more clearly;

Fig. 6 is a plan view showing a portion of the billet table illustratedin Fig. 5 and shows the positions of the billet clamping devices when abillet is released and turned;

Fig. 7 is an enlarged, fragmentary, cross-sectional view of the billettable shown in the preceding figures and is taken along the linedesignated by the numerals 77 in Fig. 3;

Fig. 8 is an enlarged, fragmentary, cross-sectional view of the grindingWheel and its mounting shown in the preceding figures and is taken alongthe line 8-8 in Fig. 1;

Fig. 9 is a schematic diagram illustrating the system employed in thepreferred embodiment of the invention for clamping and turning a billetand for lifting the grinding wheel;

Fig. 10 is a schematic diagram illustrating the system employed in thepreferred embodiment of the invention for reciprocating a billet and thegrinding wheel and for controlling the load on the grinding wheel;

Fig. 11 is an electric circuit diagram showing the electrical circuitswhich may be employed for controlling the grinding apparatus of myinvention; and

Fig. 12 is a perspective view of a preferred mounting arrangement forthe manual controls for controlling the operation of the grindingapparatus of my invention.

Referring to Figs. 1-4 which show, respectively, side elevation, plan,front elevation and side elevation views of the preferred embodiment ofmy invention, it will be seen that a grinding Wheel 10 is mounted on arotatable shaft 11 which is mounted on a pair of bearings 12 and 13which are supported on the end of a beam 14. The grinding wheel 10 isrotated on the shaft 11 by a pulley 15 which is drivingly connected bymeans of belts 16 and a pulley 17 to an electric motor 18.

The motor 18 is secured to a platform 19 which is fastened to the beam14 at a point thereon spaced from the pivot point of the beam 14. Thebeam 14 is pivotally mounted on a frame 20 by means of a shaft 21 whichis mounted in bearings 22 and 23. As shown more clearly in Fig. 2, theshaft 21 is secured to the beam 14 by means of pins 24 and 25 which passthrough collars 26 and 27, the collars 26 and 27 being welded to plates28 and 29 which in turn are welded to the beam 14. Although shaft 21 maybe a smooth-ended shaft fitted into smooth annular bearings, itpreferably is threaded at each end and is screwed into the bearings 22and 23 which may be the nuts shown. This construction is preferredbecause it provides a larger bearing surface for a given length, and ithas been found to be most satisfactory for the purposes of my inventionbecause it also assists in maintaining the positions of the bearings 22and 23.

The bearings 22 and 23 are mounted on a pair of bearings 30 and 31 whichare slidably mounted on a pair of shafts 32 and 33 whose axes areparallel to each other. The shafts 32 and 33 are secured to the frame 20by bolts 34.

It will be noted from the drawings that the'grinding wheel 10 and itsassociated driving motor 18 are both mounted on the same side of thepivot shaft 21 and therefore their weight tends to press the beam 14downward at the side of the pivot shaft 21 on which the wheel and motorare mounted. A movable counter-weight 35 and a fixed counter-weight 36are provided on the opposite side of the shaft 21 so as tocounter-balance the weight of the wheel 10 and the motor 18. As will beseen in Figs. 1, 2 and 4, the counter-weight 35 is suspended from thebeam 14 by brackets 37 and 38 which engage the axles of flanged wheels39, 40, 41 and 42.

The counter-weight 35 is adjusted along the beam 14 by fluid actuatedcylinder and piston means 43 which comprises a cylinder 44 and a piston45 and which is mounted on the underside of the beam 14. The cylinder 44is secured to the beam 14 in any suitable manner, such as by a bracket46, and the piston rod 47 is connected to the counter-Weight 35 by apivotal coupling 48. The cylinder has a pair of flexible fluid lines 49and 50 for the purpose of admitting fluid to the cylinder and therebymoving the piston rod 47 in either of two directions.

The beam 14 is reciprocatecl on the shafts 32 and 33 by fluid actuatedcylinder and piston means 51 comprising a cylinder 52 and a piston 53.The cylinder 52 is secured to the frame 20 by means of a bracket 54 anda pin 55 passing through an extension 56 on the cylinder 52. The piston53 is connected to a piston rod 57 which is fastened to an angle bracket58 by means of a nut 59 threaded on the end thereof. The bracket 58 isbolted or otherwise secured to the plate 60 which supports the bearing23 on the bearing 31.

A billet to be ground such as billet 61 is mounted on a table 62 whichis supported on grooved wheels 63-69 which travel on rails 76 and 71 inthe form of steel rods. The grooved wheels 63-69 are also guided by apair of guide rods 72 and '73 mounted above the rails 76 and 71 andextending parallel thereto. The rails and 71 and the guide rods 72 and73 are mounted on a frame 74 and are held thereon by means of nuts 75threaded on the ends of the rails and rods. Fluid actuated cylinder andpiston means 76 comprising a cylinder 77 mounted on the underside of thetable 62 and a piston rod 78 connected thereto, is provided to move thetable 62 back and forth in a direction parallel to the longitudinal axisof the billet 61. The piston rod 78 is connected at both ends thereof tothe frame 74 by means of bolts 79 and 80 and the cylinder 77 is securedto the underside of the table 62. The cylinder 77 has a pair of flexiblefluid lines (not shown) connected thereto for supplying fluid theretoand for thereby causing the cylinder 77 and hence the table 62 to movein either of two directions along the rails 70 and 71.

The billet 61 preferably is clamped on top of the table 62 by airactuated cylinder and piston means 81 and 82, each comprising a cylinderand a piston. The cylinder and piston means 81 and 82 have piston rods83 and 84 with billet engaging members 85 and 86 attached thereto. Airunder pressure is supplied to the cylinder and piston means 81 and 82through the ports 879{) to operate the rods 83 and 84. The operation andfurther details of the billet clamping devices will be set forthhereinafter.

A quick-operating, air actuated cylinder and piston means 91 isconnected between the end of beam 14 and the foundation 92. One end ofthe means 91 is pivotally connected to a bracket 93 secured to thefoundation 92 by a pin 94, and the piston rod 95 is connected to the endof the beam 14 by a yoke 96, a pin 97 and a bracket 98. Air underpressure is supplied to the means 91 through the port 99 and isexhausted from the means 91 through the port 100. When the grindingapparatus is in operation the cylinder and piston means 91 isinoperative; that is, it exerts substantially no force on the beam 14and hence the pressure on the grinding wheel 10 is determinedsubstantially by the position of the counterweight 35. However, in theevent that it is desired to lift the grinding wheel 10 quickly eitherfrom the billet 61 or because the wheel has overrun the billet, then airunder pressure is supplied to the means 91 through the port 99, and'theend of the beam 14 to which the rod 95 is attached is moved downwardly.

A handle 101 may be attached to the end of the extension 14 a of thebeam 14 for the purpose of manually adjusting the position of thegrinding wheel 10 when automatic operation is not desired. The grindingwheel 10 may also be covered with a hood 102 to provide protection foran operator.

An exhaust fan 103 having a flexible tube 104 which terminates in a hood105 may be provided for removal of the particles and dust produced bythe grinding wheel 10 during the grinding operation.

Referring to Figs. 2, and 6, it will be seen that the cylinder andpiston means 81 and 82 are mounted on plates 114 and 115 secured to thetable 62 so that the axes of the piston rods 83 and 84 intersect theaxis of the billet 61 at an acute angle. The rods 83 and 84 arepivotally connected to the billet engaging members 85 and 86 by means ofyokes 106 and 107 and pins 108 and 109 so that the members 85 and 86 canpivot with respect to the rods 83 and 84. The billet-engaging members 85and 86 are also pivotally mounted at one end on slidable end clamps 110and 111 and they carry at the opposite ends rollers 112 and 113 whichengage the side of the billet 61.

The end clamps 110 and 111 slide in slots provided in the mountingplates 114 and 115 and they are urged away from the billet 61 by springs116 and 117, which are secured to the mounting plates 114 and 115 by thethreaded bolts 118 and 119 and the brackets 120 and 121.

When the piston rods 83 and 84 are drawn away from the billet 61 by thecylinder and piston means 81 and 82, the end clamps 110 and 111 moveaway from the billet 61 because of the action of the springs 116 and 117and, in addition, the billet-engaging members 85 and 86 move away fromthe billet 61 and pivot to the positions shown in Fig. 6. Thus, thebillet 61 is completely free and may be rotated or may be removed fromthe table 62. However, when the piston rods 83 and 84 are moved towardthe billet 61 by the cylinder and piston means 81 and 82, the members 85and 86 first pivot until the rollers 112 and 113 are in contact with theside of the billet 61. Then, as the rods 83 and 84 continue tomove'toward the billet 61, the rollers 112 and 113 rotate and move alongthe length of the billet 61 and the end clamps 110 and 111 move againstthe ends of the billet 61. In this manner, the billet 61 is clamped bothat its ends and at its sides, the billet-engaging members 85 and 86forcing the billet 61 against a stop 122 which may take the shape of anangle bracket extending almost the full length of the billet 61. Thepressure which the rollers 112 and 113 exert against the side of thebillet 61 before the billet is clamped at its ends by the end clamps 110and 111 may be adjusted by adjustment of the threaded bolts 118 and 119which control the forces exerted by the springs 116 and 117 on the endclamps 110 and 111.

In the preferred embodiment of the invention the grind ing apparatus isalso provided with power-operated billet turning equipment. Referringparticularly to Figs. 5, 6 and 7, it will be seen that a fluid actuatedcylinder and piston means 123 comprising a cylinder 124 and a piston 125is mounted on the under side of the table 62. A turning finger 126 issecured to the piston 125 so that when fluid such as air is introducedinto the cylinder 124 through the line 127 the finger 126 moves upwardlyand engages the billet 61 on the under side thereof at a point in frontof its center of gravity. If the billet 61 has been released by the endclamps 110 and 111 and the billetengaging members 85 and 86, the finger126 will, as it continues to move in the upward direction, tilt thebillet 61 into such a position that it finally falls on the side whichwas previously engaged by the rollers 112 and 113. Movement of thebillet 61 away from the stop member 122 is limited by the stop member128, and the position of the billet 61 after it has been turned through90 degrees is indicated in Pig. 6. Subsequent operation of the clampingcylinder and piston means 81 and 82 pushes the billet 61 into engagementwith the stop member 122, in which position it is ready for grinding ona new surface. Similar 6 billet turning apparatus is described in mycopending application Serial No. 23l,097, filed June 12, 1951 andentitled Billet Grinder, now abandoned.

In the preferred form of the invention the grinding wheel 10 is mountedso that it may be removed without removing the shaft 11 on which it ismounted and without disconnecting the shaft 11 from the motor 18.Referring to Fig. 8, it will be seen that the grinding wheel 10 ismounted on a pair of flanges 128 and 129 which are pressed together andagainst the grinding wheel 10 by a nut 13% threaded on the end of theshaft 11, the flange 128 being held in its proper position on the shaft11 and caused to rotate therewith by a pair of tapered bushings 131 and132. The tapered bushing 132 is keyed to the shaft 11. When it isnecessary to remove the grinding wheel 10, it may be removed readily bythe mere unscrewing of nut and removal of washer 133 and flange 129, thecover 102 also being removed if desired or required by the size of thegrinding wheel 10.

The various fluid actuated cylinder and piston means mentioned above maybe actuated by air or by a liquid, such as oil, under pressure. In thepreferred form of the invention the cylinder and piston means employedfor the reciprocation of the table 62, the beam 14- and thecounterweight 35 are actuated by oil under pressure, and the cylinderand piston means employed for the rapid lifting of the grinding wheel10, the turning of the billet 61 and the clamping of the billet 61 areactuated by air, air being preferred for the operation of thesecylinders and piston means because of the speed and cushioning effectobtainable.

Fig. 9 illustrates schematically the controls and connections for theair actuated cylinder and piston means. In this figure it will be seenthat the air under pressure for operation of the safety release orgrinding wheel lifting cylinder and piston means 91 is supplied theretothrough a line 134 after passing through an air flow regulator 135, asolenoid controlled valve 136, line 137, an air pressure regulator andfilter 139, line and line 141, the last-mentioned line being connectedto a source of air under pressure. Thus, when solenoid 142 is actuatedby controls to be described hereinafter, air is admitted into the upperportion of the cylinder and piston means 91 causing the piston rod 95 tomove rapidly downward, and when the solenoid 142 is de-energized, thepiston rod $5 is released and assumes a position determined by theposition of the counterweight 35 on the beam 14.

Air under pressure is supplied to the billet turning cylinder and pistonmeans 123 through the line 143, an air pressure regulator and filter144, line 145, line 146, a solenoid actuated valve 147, an air flowregulator 148 and line 149. When the solenoid 15%) is suitablyenergized, air flows into the lower part of the cylinder and pistonmeans 123 and causes the billet turning finger 126 to move upwardly, andwhen the solenoid 150 is tie-energized, the supply of air to the means123 is cut off and the finger 126 drops below the top of table 62.

Clamping cylinder and piston means 81 and 82 are double acting andpreferably are controlled through a foot-operated valve shownschematically at 151. Air under pressure and supplied by line 145 isdiverted to either line 152 or 153, as required, by the valve 151causing the rods 83 and 84 to move outwardly from or inwardly to thecylinders, depending upon whether the air is diverted to line 152 orline 153, respectively. Preferably, valve 151 is of the type which uponone depression of the foot lever 154 causes the air to be diverted intoone of the lines 152 and 153 and upon the next depression of the lever154 causes the air to be diverted into the other of the lines 152 and153.

In Fig. 10 there is shown schematically the oil operated cylinder andpiston means and their connections both with the valves which produceoperation thereof and the electrical controls which are operatedthereby. Referring to Fig. 10, oil is supplied under pressure by a motor155 and a pump 156 from a reservoir 157. The oil is conveyed to thecylinder and piston means over the lines 158, 159, 160 and 161, line 158being provided with a pressure relief valve 162 and lines 159, 161) and161 being provided with shut-oi valves 163, 164 and 165. The supply offluid to the cylinder and piston means 43, 76 and 51 is controlledrespectively by electrically operable valves 166, 167 and 168. The valve166 is provided with a pair of solenoids 169 and 170 which operate thevalve, and pressure relief valves 171 and 1'72 are connected betweenvalve 166 and cylinder and piston means 13. The valves 167 and 168 arealso equipped with pairs of solenoids 173174 and 175-176, and pressurerelief valves 177, 173, 179 and 182 are connected in the lines betweenthe valves 167 and 168 and the cylinders 51 and 76.

The solenoids 169 and 170 of valve 166 are controlled by the circuitshown in Fig. 11 and described in connection therewith, and the valves16", and 163 are controlled respectively by the limit switches 131182mounted on the frame 74 to the rear of table 62 (see Figs. 1, 4 and and133-184 mounted on the frame 29 to the left of the beam 14 (see Figs. 1and 2). Limit switches 181 and 182 are actuated by a pair of stops 185and 136 which are carried by the end clamps 116 and 111, as is bestshown in Fig. 5, and safety lift switches 187 and 188 are controlled bya pair of adjustable stops 189 and 190, these latter stops being mountedon the stationary frame 74 which supports the table 62 (see Figs. 2 and5). As will be described hereinafter in greater detail, safety liftswitches 187 and 188 control the operation of the safety release or liftcylinder 91 and are mounted on the front of the table 62 (see Figs. 3and 5).

Limit switches 133 and 184 are operated by a stop 191 which may take theform of a V-shaped plate, shown more clearly in Figs. 1 and 2. Switches192 and 193 are also mounted on the frame to the right of the beam 14,as indicated in Figs. 2 and 4, and are operated by a cam 194 also shownin Figs. 2 and 4. These switches 192 and 193 are employed in connectionwith relay 195 to reduce the pressure on the grinding wheel 10 beforethe wheel reaches the corners of the billet 61 and their operation willbe described in greater detail in connection with Fig. 11. Relay 195 hascontacts 196 and 197 and is connected in series with the switches 192and 193 and the source 198.

A limit switch 199 is mounted on the end of beam 14, as it best shown inFig. 4, and is engageable with the bracket 37 which supports thecounter-weight so as to de-energize the solenoid 169 when thecounterweight 35 is at its rearmost position.

Referring to Fig. 1], which is an electrical circuit diagram of theelectrical system employed for controlling the grinding apparatus of myinvention, it will be seen that the motor 18 is connected to athree-phase source through contacts 260 which are controlled by themanually operable switches 201 and 292. In accordance with one featureof my invention, the force applied to the grinding wheel 18 to hold itagainst the billet 61 is automatically adjusted in accordance with theload on the grinding wheel 10. To accomplish this, I employ the circuitshown in the upper left-hand side of Fig. 11. A transformer 263, whichmay be, for example, a current transformer, is coupled to the inputcircuit of the motor 18 and when the motor 18 is in operation voltage isproduced across the secondary of the transformer 2413 which is shuntedby a reactance 2194, a manually variable resistor 205 in series with afixed resistor 206 and the primary 2 .17 of the transformer 208. Thesecondary 209 of the transformer 203 is connected to diagonally oppositepoints on a bridge rectifier 210 which comprises dry rectifiers 211,212, 213 and 214, which may, for example, be selenium or copper oxiderectifiers. The output of the bridge rectifier 210 is connected to theenergizing coil 215 of a three-position relay 216' which may be shuntedby a filter condenser 217. This relay 216 has two pairs of contacts218219 and 220221 and an armature 2-22. The armature 222 is connected toan adjustable spring 223 which causes the armature 222 to connect thecontacts 220 and 221 unless the coil 215 is energized to at least apredetermined extent by the rectifier 210. Thus, when only a smallcurrent is flowing through the coil 215, the contacts 220 and 221 areconnected together by the armature 222, but when the current exceeds apredetermined level, determined by the sensitivity of the relay 216 andthe tension on the spring 223, contacts 229 and 221 are disconnected. Asthe current through coil 215 is further increased, the armature 222moves toward the contacts 218 and 219 until finally when a secondpredetermined current level is reached the contacts 218 and 219 areconnected together.

When the handle 224 of the variable resistor 205 is in the verticalposition shown, the contacts 225 and 226 are connected together by thecontactor 227 which is moved into its downward position by the actuator223 on the end of the handle 224 and the contacts 229 and 231) areconnected together by the contactor 231, but when the handle 224 ismoved from the vertical position shown to some position such as the oneshown in dotted lines the contacts 225 and 226 are disconnected and thecontacts 232 and 233 are connected together by the contactor 231. In thevertical position of the handle 224 the automatic operation of thegrinding apparatus is discontinued and the grinding wheel 11? iscompletely lifted off the billet 61, but when automatic operation isdesired, the handle 224 is moved from the vertical position and thecontacts 218 and 220 are connected to terminal B of the power source.

Contact 219 is connected to one end of the solenoid or coil 169 employedto actuate the valve 166 and the opposite end of solenoid 169 isconnected to terminal A. Also, contact 221 is connected to one end ofsolenoid or coil which operates the valve 166 in the opposite directionand the other end of solenoid 11 i) is connected to the terminal A.Thus, when contacts 213 and 219 are connected together by the armature222, a circuit for the solenoid 169 which actuates the valve 166 in sucha direction that the counter-weight 35 is moved rearwardly of the beam14, and hence in such a direction that the force on the grinding wheel10 is decreased, is established from terminal B of the power sourcethrough contacts 232 and 233, contactor 231, contacts 218 and 219,solenoid 169 and back to terminal A. However, when contacts 220 and 221are connected together by armature 222, a circuit is completed forenergizing solenoid 170 (which moves the counter-weight 35 toward thegrinding wheel 10) from terminal B through contacts 232 and 233,contactor 231, contacts 220 and 221., solenoid 170 and back to terminalA. When the armature 222 is in a position intermediate the contacts 22221 and 2l8219, neither of the pairs of contacts is connected togetherand hence neither of the solenoids 169 and 170 is energized. Whenneither solenoid 169 and 170 is energized, the counter-weight 35 remainsin a fixed position.

Since the current in coil 215 varies with the current in the inputcircuit of the motor 13, the position of the counter-weight 35 iscontrolled by the current in the input circuit of motor 18 and hence bythe energy consumed by the motor 18. Consequently, when the inputcurrent to the motor 18 is increased above a predetermined value becauseof an increase in the load on the grinding wheel 10, the valve 166 isoperated so that the counter-weight 35 moves away from the grindingwheel 10. Also, when the input current to the motor 18 decreases below apredetermined value because of a decrease in the load on the grindingwheel 10, the valve 166 is operated so that the counter-weight movestoward the grinding wheel 10. In this manner, the load on the motor 18,and hence the rate at which material is removed from the billet 61, andthe load on the grinding wheel may be maintained at a substantiallyconstant value.

The value of the load on the motor 18 may be adjusted by adjustment ofthe spring 223 and by adjustment of the position of the handle 224.Adjustment of the handle 224 changes the value of the resistor 205 inseries with the resistor 206 and hence changes the voltage at theprimary 207 at the transformer 208. Thus, if the handle 224 is moved tothe position shown in dotted lines, the value of the resistor 205 isdecreased and the voltage at the primary winding 207 is correspondinglydecreased. When the handle 224 is in the vertical position shown, theresistor 205 has its maximum value and hence the voltage at the primarywinding 207 is at its maximum value. The current in the coil 215 changeswith and in the same direction as the voltage across the primary winding207.

In accordance with a further feature of the invention, the downwardforce on the grinding wheel 10 is reduced as the grinding wheel 10approaches the forward and rear corners of the billet 61. This featureis desirable not only because it prevents sudden dropping of thegrinding wheel if it goes over the front and rear corners of the billet61, but also because it reduces rounding of these corners of the billet.Adjustable resistor 234, relay 195 and its associated armature 235 andcontact 196 and switches 192 and 193 are provided to accomplish thiscontrol of the force on the grinding wheel 10.

Referring to Fig. 4, the switches 192 and 193 which are adjustablymounted on the frame 20 are adjusted to such positions that switch 192is operated by cam 194 when the billet contacting surface of thegrinding wheel 10 is close to the forward edge of the billet 61 and theswitch 193 is operated by the cam 194 when the billet contacting surfaceof the grinding wheel 10 is close to the rear corner of the billet 61.Referring again to Fig. 11, the relay 195 normally is energized by acircuit which may be traced from terminal A through switches 192 and193, through the coil of relay 195 and back to terminal B. When therelay 195 is energized, the armature 235 is pulled up against contact196 and hence the resistor 234 is shorted out. With resistor 234 shortedout, the voltage at the primary winding 207 is determined by the settingof handle 224 and resistor 206 and hence the downward force on thegrinding wheel 10 is determined by the setting of the handle 224.However, when either of the switches 192 and 193 is operated by the cam194, the energizing circuit for relay 195 is broken and the armature 235falls back against contact 197. The resistance then appearing betweenthe leads 237 and 238 is increased by the value of the resistance 234.Because of the increase of resistance between leads 237 and 238 a largervoltage will appear across the primary 207 than when the resistor 234 isshorted out. A larger voltage across the primary 207 produces a largercurrent in the coil 215 and pulls armature 222 against contacts 218 and219 closing the circuit for the solenoid 169 which, as explainedpreviously, moves the counter-weight 35 rearwardly away from thegrinding wheel 10 and reduces the downward force on the grinding wheel10. As soon as the counter-weight 35 has moved rearwardly enough toreduce the downward force on the grinding wheel 10, and hence the inputcurrent to the motor 18, an amount sutficient to compensate for theincrease in current pro duced in coil 215 by the insertion of theresistor 234 in series with resistors 205 and 206, the armature 222 willresume its intermediate position and the counter-weight 35 will stop. Itis thus apparent that when either of the switches 192 and 193 isoperated, the downward force on the grinding wheel 10 is decreased andthe amount of decrease is determined by the setting of control 239 forresistor 234.

. 10 above and from an examination of the circuit diagram in Fig. 11that the downward force on the grinding wheel 10 may be manuallyadjusted at any time during the operation of the grinding apparatus bymovement of the handle 224. In its position nearest the horizontal, thehandle will cause the wheel 10 to press with maximum force against thebillet 61 and, as the handle 224 is moved toward the vertical positionshown in solid lines, the downward force is decreased until in someposition just prior to the vertical position the minimum force which itis possible to obtain with an automatic control circuit is applied tothe grinding wheel 10. However, the circuit shown is so arranged that bymotion of the handle 224 into its vertical position the counter-weight35 is moved to the rear end of the beam 14. When the counter-weight 35is at the rear end of the beam 14, the wheel 10 is completely liftedfrom the billet 61, and normally the grinding wheel is in this positionwhen the grinding apparatus is idle. Therefore, it is desirable thatwhen the counter-weight 35 is in its rearmost position, the

solenoid 169 is de-energized. To accomplish this result the arm 228 onthe handle 224 moves contactor 227 against contacts 225 and 226,connecting contacts 225 and 226 together, and the arm 228 permits thecontactor 231 to connect contacts 229 and 230 together. Thus, a circuitmay be traced from terminal B through contacts 229 and 230, contactor231, switch 199, contacts 225 and 226, contactor 227, solenoid 169 andback to terminal A, and when the handle 224 is first moved to thevertical position, the solenoid 169 is energized causing thecounterweight 35 to move rearwardly along the beam 14. However, when thecounter-weight 35 reaches its rearmost position, it operates switch 199and opens the last-mentioned energizing circuit for solenoid 169. Thecounterweight 35 remains in the rearmost position until the handle 224is again moved from its vertical position and places the counter-weight35 under the automatic control circuit previously described.

Solenoids 1'73 and 1'74 which control the operation of valve 167, andhence the reciprocation of the table 62, may be energized throughmanually operable switches 246 and 241, through contactor 242 rotatableby motor 243 and through the table controlled switches 181 and 182.Switches 240 and 241 are provided in the event that it is desired tocontrol the reciprocation of the table 62 manually and the switches 181and 182 are provided for automatic control of the table reciprocation.Referring to Fig. 5, it will be seen that the switches 181 and 182 areadjustably mounted on the frame 74 and are engageable with cams 185 and186 which are mounted on the end clamps and 111. By the mounting of thecams and 186 on the end clamps, they are moved with the end clamps andhence they always operate the switches 181 and 182 when the wheel 10reaches the end of a billet, even though different billets may havesmall differences in length. Switch 181 is mounted on the frame 74 insuch a position that it is operated when the end of the billet 61adjacent the end clamp 110 is under approximately the center of the faceof the grinding wheel 10, and the switch 182 is mounted on the frame '74in such a position that it is operated by the cam 136 when the end ofthe billet 61 adjacent the end clamp 111 is under the center of the faceof the grinding wheel 10. Thus, when the grinding Wheel 10 reaches anend of the billet 61, one of the two switches 181 and 182 is operatedand energizes the corresponding solenoid 173 or 174 causing the table 62to reverse its direction of movement.

If there is a portion of the surface of the billet 61 which requiresadditional grinding, a relatively short reciprocatory stroke of thetable may. be provided by operation of the timer control switch 245 andthe control 246 on the timer motor speed control apparatus 247, thelatter apparatus being connected to the motor It will also be apparentfrom a consideration of the 75 243 and used to control the speedthereof. Operation 11 of the switch 245 supplies electrical energy tothe contactor 242 which alternately energizes solenoids 173 and 174 andthe speed of the motor 243 as adjusted by the control 246 determines thetimes at which solenoids 173 and 174 are alternately energized and hencethe length of the path of movement of the table 62.

Switches 243 and 249 are provided for manual control of thereciprocation of the beam 14, and switches 133 and 184, as indicatedpreviously, provide automatic control of the reciprocation of the beam14. Referring to Fig. 1, it will be seen that switches and 184 aremounted on the frame 24 and are so positioned with respect to the cam191 that switch 184 is operated when the portion of the face of the wheewhich contacts the billet 61 is at the forward corner of the billet 61and that the switch 13-3 is operated by the com 191 when the face of thewheel 10 which contacts the billet 61 is at the rear corner of thebillet 61. Thus, as the contacting portion of the wheel 10 reaches theforward corner of the billet 61, the direction of motion of the beam 14is reversed and, when the contacting surface reaches the rear corner ofthe billet 61, the direction of motion of the beam 14 is again reversed.The positions of the switches 133 and 134 may be adjusted so as toaccommodate billets of different width.

A manually operable switch f) is provided so that switches 181, 132, 133and 184 may be disabled when it is desired to stop the automaticreciprocation of the beam 14 and the table 62. With switch 259 in itsoff position the manual switches 24), 241, 248 and 249 may be employedto position the beam 14 or the table 62.

The billet turning solenoid or coil 1 may be energized by operation ofthe manually operable switch 251, and when operated, the billet turningfinger 126 engages and lifts the billet 61 as previously described.

The safety lift solenoid or coil 142 may be energized by the switches137 and 138 which are mounted on the front of the table 62 (see Fig. 5)and it may be energized by the manually operable switch 252. Switches187 and are provided so that if the wheel 1%) passes beyond the end of abillet one of the switches 1.37 and 188 is operated and energizes relay253 which has armatures 254 and 255 and contacts 256 and 257. When relay253 is energized it pulls armature 254 against contact 56 and armature255 against contact 257. Engagement of the armature 255 with the contact257 closes an energizing circuit for the relay 253 and keeps the relay253 operated until the relay is reset by the switch 252, as indicatedhereinafter. Armature 254, when pulled against the contact 256, closesan energizing circuit for the solenoid 142 and hence causes operation ofthe air actuated cylinder and piston means 91. As previously described,the air actuated cylinder and piston means 91 pulls the rear of the beam14 downwardly and lifts the wheel i off the billet 61 and above the endclamps 11d and 111.

If one of the switches 187 and 188 is operated, the cylinder and pistonmeans 91 remains operated as long as the relay 253 is energized. Becauseof the holding circuit through armature 255 and contact 257, the relay253 remains energized until switch 252 is operated to its reset positionin which the contacts 258 and 259 are connected together. When contacts258 and 259 are connected together, the relay 253 is short-circuited andthe armatures 254 and 255 fall back against their idle contacts.

if at any time it becomes necessary to lift the wheel it quickly fromthe billet 61, the manually operable switch 252 may be operated to itslift position so as to connect contacts 260 and 261 together. Operationof the switch 252 in this manner also energizes the safety lift solenoid142 and actuates the cylinder and piston means 91. However, as soon asthe switch 252 is returned to its intermediate or rest position, thesolenoid 142 is deenergized and cylinder and piston means 91 becomesidle.

If desired, switches 187 and 188, or additional switches connected inthe same manner as these switches, may be mounted on the frame 20 andoperated by a cam carried by the reciprocating means for beam 14 so asto lift the wheel 10 if the wheel 10 passes beyond a corner of thebillet 61.

Transformer 262 is provided for the purpose of supplying the requiredvoltage to the relay 253 and may be omitted if a relay operating at thevoltage of the source connected to terminals A--B is employed.

Fig. 12 illustrates the preferred arrangement of the manually operablecontrols employed in connection with the grinding apparatus of myinvention. In this figure, the handle 224 which controls the grindingwheel pressure is mounted on the side of a cabinet 263 which houses thevarious manual switches. The grinding motor control switches 201 and 202and the safety lift cylinder and piston means operating and reset switch252 may be mounted on the front of the cabinet 263.

The cabinet 263 is provided with a sloping panel 264 on which the manualtable reciprocation control switches 246 and 241, the billet turningswitch 251, the beam and table reciprocation on-off switch 250, thetimer energizing switch 245 and the beam reciprocation control switches248 and 249 are mounted.

The billet clamping control valve 151 may be separately mounted adjacentthe pedestal 265 of the cabinet 263 so that all of the controls arewithin easy reach of an operator.

From the above it will be seen that when the appropriate switches areoperated the table 62 is reciprocated along a path which is parallel tothe axis of the grinding wheel 10 and the grinding wheel 10 isreciprocated crosswise of the table 62. The rate at which the table 62and the beam 14 are reciprocated may be controlled by controlling thepressure of the fluid supplied to the cylinders 76 and 43 and bycontrolling the rate at which the fluid is supplied to these cylinders.In the preferred form of the invention the grinding wheel 10 and thebeam 14 are moved at a relatively slow rate and the table 62 is moved ata relatively rapid rate so that the table 62 is moved back and forthseveral times during the time it takes the grinding wheel 10 to movefrom the rear corner of the billet 61 to the front corner of the billet61.

Once the switches 183, 184, 192, 193, 181 and 182 have been set to thepositions described above, the grinding wheel 10 will completelytraverse the surface of a billet one or more times without any action onthe part of an operator. When the surface of a billet has been ground tothe desired extent, the automatic reciprocation of the table 62 and thebeam 14 is discontinued, and the billet is unclamped, turned andreclamped so that a new surface of the billet may be ground by a similaroperation.

Although I have illustrated and described the load controlling apparatusof my invention in connection with a grinding wheel that is mounted on apivotally mounted beam, it will be apparent that such controllingapparatus may also be used to control the load on a grinding wheelmounted in other ways. Also, it will be apparent to those skilled in theart that the stops and limit switches for controlling the reciprocationof the beam 14 and the table 62 and for controlling the lifting of thegrinding wheel 10 may be differently arranged.

Having thus described my invention with particular reference to thepreferred form thereof, it will be obvious to those skilled in the artto which the invention pertains, after understanding my invention, thatvarious changes and other modifications may be made therein withoutdeparting from the spirit and scope of my invention, as defined by theclaims appended hereto.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. Apparatus for surface grinding billets comprising:

spanned a pivotally mounted beam, means for mounting an abrasivegrinding wheel on said beam, grinding wheel driving means, means forreciprocating said beam with respect to a billet and in a directiontransverse to the axis of said wheel, means for rotating said beam aboutits pivot and means connected to said rotating means for actuating saidrotating means in accordance with the load on said driving meanscomprising control means connected to said driving means and operable bythe energy supplied thereto.

2. Apparatus for surface grinding billets comprising: a pivotallymounted beam, means for mounting an abrasive grinding wheel on saidbeam, grinding wheel driving means, means for reciprocating said beam ina direction transverse to its pivot, adjustable means for rotating saidbeam about its pivot point and means for actuating said adjustable meansconnected thereto and comprising control means connected to said meansfor driving said wheel and operable by the energy supplied thereto.

3. Apparatus for surface grinding billets comprising: a pivotallymounted beam, an abrasive grinding wheel mounted on said beam at aposition spaced from the pivot point of said beam, an electric motormounted on said beam and drivingly connected with said wheel, acounterweight movably mounted on said beam on the opposite side of saidpivot point from said wheel and means for varying the load on said wheelcomprising electrically controlled means connected to saidcounter-weight for adjusting the position thereof, said electricallycontrolled means also being connected to the input circuit of said motorand responsive to the flow of current therein, whereby saidcounter-Weight moves away from said pivot point with an increase incurrent and moves toward said pivot point with a decrease in current.

4. Apparatus for surface grinding billets comprising: a pivotallymounted beam, an abrasive grinding wheel mounted on said beam at aposition spaced from the pivot point of said beam, an electric motormounted on said beam on the same side of said pivot point as said wheeland drivingly connected with said wheel, a counter-weight movablymounted on said beam on the opposite side of said pivot point from saidwheel and means for varying the load on said wheel comprising fluidactuated cylinder and piston means mounted on said beam and connected tosaid counter-weight, electrically actuated control means connected tosaid cylinder and piston means for controlling the supply of fluidthereto and for thereby causing said piston to move with respect to saidcylinder in either of two directions and electrical switching meansconnected to said control means for causing operation of said con trolmeans, said switching means being connected to the input circuit of saidmotor and being responsive to current flow therein.

5. Apparatus for surface grinding billets comprising: a pivotallymounted beam, an abrasive grinding wheel mounted on said beam at aposition spaced from the pivot point of said beam, an electric motormounted on said beam on the same side of said pivot point as said wheeland drivingly connected with said wheel, a counter-weight movablymounted on said beam on the opposite side of said pivot point from saidwheel and means for varying the load on said wheel comprising fluidactuated cylinder and piston means mounted on said beam and connected tosaid counter-weight, control means connected to said cylinder and pistonmeans for controlling the supply of fluid thereto for alternativelymoving the piston with respect to the cylinder in either of twodirections and electrical connections between said motor and saidcontrol means for causing operation of said control means in response tothe electrical current drawn by said motor, whereby said control meansin cooperation with said cylinder and piston means causes saidcounter-weight to move away from said pivot point with an increase incurrent drawn and causes said counter-weight to move toward said pivotpoint wtih a decrease in current drawn.

6. Apparatus for grinding billets comprising a pivotally mounted beam,means for moving said beam in a direction transverse to its pivot, meansfor mounting a grinding wheel on said beam, an electric motor fordriving said wheel, and means for controlling the position of saidmounting means with respect to a billet comprising a movable weightmounted on said beam, moving means connected to said weight for movingthe weight along the beam, electrically operable control means connectedto said moving means for controlling the operation thereof, and meansfor operating said control means comprising relay means connected to theinput circuit of said motor and to said control means, said relay meansbeing operable by the current in said input circuit of said motor.

7. Apparatus for grinding billets comprising means for movably mountinga grinding wheel, an electric motor for driving said wheel, and meansfor controlling the position of said mounting means with respect to abillet comprising fluid actuated cylinder and piston means connected tosaid mounting means, an electrically operable valve connected to saidcylinder and piston means for controlling the supply of fluid thereto, atransformer coupled to the input circuit of said motor, a rectifierconnected to said transformer, and means for operating said valvecomprising relay means connected to said rectifier, and to said valve,said relay means being operable by the output of said rectifier.

8. Apparatus for grinding billets comprising means for movably mountinga grinding wheel, an electric motor for driving said wheel, and meansfor controlling the position of said mounting means with respect to abillet comprising fluid actuated cylinder and piston means connected tosaid mounting means, an electrically operable valve connected to saidcylinder and piston means for controlling the supply of fluid theretoand having a pair of energizing coils, means for supplying energy tosaid coils, a transformer coupled to the input circuit of said motor, arectifier connected to said transformer, and three-position relay meansconnected to said rectifier, to said coils and to said means forsupplying energy to said coils, said relay means being controllable inposition by the output of said rectifier and in a first position thereofconnecting one of said energizing coils to said means for supplyingenergy thereto, in a second position thereof connecting the other ofsaid energizing coils to said means for supplying energy thereto, and ina third position thereof disconnecting said coils from said means forsupplying energy thereto.

9. Apparatus for surface grinding billets comprising: a movable tablefor supporting a billet and means for reciprocating said table connectedthereto; a pivotally and movably mounted beam, said beam being mountedwith its pivot axis substantially parallel to the path of travel of saidtable, and an abrasive wheel mounted on said beam; means for drivingsaid wheel; a counter-weight movably mounted on said beam, meansconnected to said driving means and to said weight and responsive to thepower consumption of said driving means for adjusting the position ofsaid weight in accordance with the load on said wheel, and meansconnected to said beam for reciprocating said beam in a directiontransverse to the direction of movement of said table.

10. Apparatus for surface grinding billets comprising: a movable tablefor supporting a billet, means for reciprocating said table connectedthereto, and control means connected to and actuated by saidreciprocating means in predetermined positions thereof forcontrollingthe movements thereof; a pivotally and movably mounted beam, said beambeing mounted with its pivot axis substantially parallel to the path oftravel of said table, and an abrasive wheel mounted on said beam on oneside of said pivot axis; means for driving said wheel; a counter-weightmovably mounted on said beam, means connected to said weight foradjusting the position thereof and control means connected to saidlast-mentioned means for actuation thereof in accordance with the loadon said wheel,

said last-mentioned control means also being connected to said drivingmeans and responsive to the power consumption thereof; means connectedto said beam for reciprocating said beam in a direction transverse tothe direction of movement of said table, and control means connected toand actuable by said last-mentioned reciprocating means in predeterminedpositions thereof for controlling the movements thereof.

11. Apparatus for surface grinding billets comprising: a movable tablefor supporting a billet, means for reciprocating said table connectedthereto, and control means connected to and actuated by saidreciprocating means in predetermined positions thereof for controllingthe movements thereof; a pivotally and movably mounted beam, said beambeing mounted with its pivot axis substantially parallel to the path oftravel of said table, an abrasive wheel mounted on said beam on one sideof said pivot axis and an electric motor drivingly connected with saidwheel and mounted on said beam; a counterweight movably mounted on saidbeam, means connected to said Weight for adjusting the position thereofand control means connected to said last-mentioned means for actuationthereof in accordance with the load on said wheel, said last-mentionedcontrol means also being electrically connected to said electric motorand responsive to the load current thereof; and means connected to saidbeam for reciprocating said beam in a direction transverse to thedirection of movement of said table, and control means connected to andactuable by said last-mentioned reciprocating means in predeterminedpositions thereof for controlling the movements thereof.

12. Apparatus for surface grinding billets comprising: a movable tablefor supporting a billet and means for moving said table in apredetermined direction comprising fluid actuated cylinder and pistonmeans connected to said table, control means connected to said cylinderand piston means for controlling the supply of fluid thereto and forcausing movement of said table in said direction and adjustable stopmeans engageable with said control means in different positions of saidtable for operating said control means, one of said two last-mentionedmeans being connected to and movable by said table; a pivotally andmovably mounted beam, said beam being mounted with its pivot axissubstantially parallel to the direction of travel of said table, anabrasive wheel mounted on said beam on one side of the pivot pointthereof, and an electric motor drivingly connected with said wheel andmounted on said beam on the same side of said pivot point as said wheel;a counter-weight movably mounted on said beam on the side of said pivotpoint opposite from said wheel, fluid actuated cylinder and piston meansconnected to said veight for moving said Weight and means for adjustingthe position of said weight in accordance with the load on said Wheelcomprising control means connected with said last-mentioned cylinder andpiston means for controlling the supply of fluid thereto, saidlast-mentioned control means also being electrically connectcd to saidelectric motor and responsive to the load current thereof to change thesupply of fluid to said lastmentioned cylinder and piston means, andmeans for reciprocating said beam in a direction transverse to thedirection of movement of said table comprising fluid actuated cylinderand piston means connected to said beam, control means connected to saidlast-mentioned cylinder and piston means for controlling the supply offluid thereto and adjustable stop means engageable with saidlastrnentioned control means in different predetermined positions ofsaid beam for operating said last-mentioned control means, one of saidtwo last-mentioned means being connected to and movable by said beam.

13. Apparatus for surface grinding billets comprising: a stationaryframe, a table movably mounted on said frame for supporting andreciprocating a billet, and means for moving said table in either of twoopposite directions comprising fluid actuated cylinder and piston meansconnected between said table and said frame, control means mounted onsaid table for controlling the supply of fluid to said cylinder andpiston means and adjustable stop means mounted on said frame andengageable with said control means in different predetermined positionsof said table for operating said control means; a further stationaryframe, a beam pivotally and movably mounted on said further frame, saidbeam being movable in a direction transverse to the direction ofmovement of said table, an abrasive wheel mounted on one end of saidbeam and an electric motor drivingly connected with said wheel andmounted on said beam on the same side of the pivot point of said beam assaid wheel; a counter-weight movably mounted on said beam on the side ofsaid pivot point opposite from said wheel, fluid actuated cylinder andpiston means mounted on said beam and connected to said weight foradjusting the position thereof and control means connected to saidlastmentioned cylinder and piston means for controlling the supply offluid thereto, said last-mentioned control means also being electricallyconnected to said electric motor and responsive to the load currentthereof to change the supply of fluid to said last-mentioned cylinderand piston means; and means for reciprocating said beam in a directiontransverse to the direction of movement of said table comprising fluidactuated cylinder and piston means connected,.,between said furtherframe and said beam, control means mounted on said further frame forcontrolling the supply of fluid to said last-mentioned cylinder andpiston means and adjustable stop means movable by said last-mentionedcylinder and piston means and engageable with said last-mentionedcontrol means in different predetermined positions of said beam foroperating said last-mentioned control means.

l4. Apparatus for surface grinding billets comprising: a stationaryframe, a table movably mounted on said frame for supporting andreciprocating a billet, and means for moving said table in either of twoopposite directions comprising fluid actuated cylinder and piston meansconnected between said table and said frame and operable in either oftwo directions, control means mounted on said table for controlling thesupply of fluid to said cylinder and piston means and adjustable stopmeans mounted on said frame and engageable with said control means indifferent predetermined positions of said table for operating saidcontrol means; a further stationary frame, a pair of shafts mounted inspaced and parallel relation on said further frame and secured thereto,said shafts being mounted with their longitudinal axes perpendicular tothe direction of movement of said table, a pair of bearings, eachslidably mounted on one of said shafts, a pivot shaft mounted at itsends in said bearings, a beam mounted on said pivot shaft at a pointintermediate the ends of said beam, an abrasive wheel mounted on one endof said beam with its axis of rotation extending substantially parallelto the direction of movement of said table and an electric motordrivingly connected with said wheel and mounted on said beam on the sameside of said pivot shaft as said wheel; a counter-weight movably mountedon said beam on the side of said pivot shaft opposite from said wheel,fluid actuated cylinder and piston means mounted on said beam andconnected to said weight for adjusting the position thereof and controlmeans connected to said last-mentioned cylinder and piston means forcontrolling the supply of fluid thereto, said last-mentioned controlmeans also being electrically connected to said electric motor andresponsive to the load current thereof to change the supply of fluid tosaid last-mentioned cylinder and piston means whereby the position ofsaid counter-weight is varied in accordance with said load current; andmeans for reciprocating said beam in a direction transverse to thedirection of movement of said table comprising fluid actuated cylinderand piston means connected between said further frame and said pivotshaft, control means mounted on said further frame for controlling thesupply of fluid to said lastmentioned cylinder and piston means andadjustable stop means movable by said last-mentioned cylinder and pistonmeans and engageable with said last-mentioned control means in differentpredetermined positions of said beam for operating said last-mentionedcontrol means.

15. Apparatus for surface grinding billets comprising: a stationaryframe, a table movably mounted on said frame for supporting andreciprocating a billet, and means for moving said table in either of twoopposite directions comprising fluid actuated cylinder and piston meansconnected between said table and said frame and operable in either oftwo directions, control means mounted on said table for controlling thesupply of fluid to said cylinder and piston means and adjustable stopmeans mounted on said frame and engageable with said control means indifferent predetermined positions of said table for operating saidcontrol means; means mounted on said table for clamping a billet thereoncomprising a movable billet engaging member and fluid actuated cylinderand piston means connected to said engaging member for causing movementthereof; means mounted on said table for rotating a billet about itslongitudinal axis comprising a turning finger engageable with saidbillet and fluid actuated cylinder and piston means connected to saidfinger for causing movement thereof; a further stationary frame, a pairof shafts mounted in spaced and parallel relation on said further frameand secured thereto, said shafts being mounted with their longitudinalaxes perpendicular to the direction of movement of said table, a pair ofbearings, each slidably mounted on one of said shafts, a pivot shaftmounted at its ends in said bearings, a beam mounted on said pivot shaftat a point intermediate the ends of said beam, an abrasive wheel mountedon one end of said beam with its axis of rotation extendingsubstantially parallel to the direction of movement of said table and anelectric motor drivingly connected with said wheel and mounted onsaidbeam on the same side of said pivot shaft as said wheel; acounter-weight movably mounted on said beam on the side of said pivotshaft opposite from said wheel, fluid actuated cylinder and piston meansmounted on said beam and connected to said weight for adjusting theposition thereof and control means connected to said last-mentionedcylinder and piston means for controlling the supply of fluid thereto,said last-mentioned control means also being electrically connected tosaid electric motor and responsive to the load current thereof to changethe supply of fluid to said last-mentioned cylinder and piston meanswhereby the position of said counter-weight is varied in accordance withsaid load current; and means for reciprocating said beam in a directiontransverse to the direction of movement of said table comprising fluidactuated cylinder and piston means connected between said further frameand said pivot shaft, control means mounted on said further frame forcontrolling the supply of fluid to said lastmentioned cylinder andpiston means and adjustable stop means movable by said last-mentionedcylinder and piston means and engageable with said last-mentionedcontrol means in different predetermined positions of said beam foroperating said last-mentioned control means.

16. Grinding apparatus comprising a table for holding a piece to beground, means for reciprocating said table connected thereto, means formounting a grinding wheel adjacent said piece, means actuated by saidreciprocating means for reversing the movement of said reciprocatingmeans the end of each reciprocatory stroke thereof and timing meansconnected to said reciprocating means, said timing means operating atpredetermined times independently of the movement of said reciprocatingmeans and being adapted to reverse the movement of said reciprocatingmeans at said times.

17. Grinding apparatus comprising a table for holding a piece to beground, means for reciprocating said table, means for mounting agrinding wheel adjacent said table,

means for reciprocating said mounting means and means for clamping saidpiece on said table comprising a first clamp member slidably mounted onsaid table, a second clamp member pivotally mounted on said first clampmember and means for forcing said second clamp member against saidpiece.

18. Grinding apparatus comprising a table for holding a piece to beground, means for reciprocating said table, means for mounting agrinding wheel adjacent said table, means for reciprocating saidmounting means and means for clamping said piece on said tablecomprising a first clamp member mounted on said table and slidable alonga predetermined path, a second clamp member pivotally mounted on saidfirst clamp member and means connected to said second clamp member forexerting a force thereon directed along a path at an angle to saidfirstmentioned path.

19. Grinding apparatus comprising a table for holding a piece to beground, means for reciprocating said table, means for mounting agrinding wheel adjacent said table, means for reciprocating saidmounting means and means for clamping said piece on said tablecomprising a first clamp member mounted on said table and slidable alonga predetermined path, a second clamp member pivotally mounted on saidfirst clamp member, means connected to said first clamp member forurging said first clamp member away from said piece and means connectedto said second clamp member for urging both said clamp members towardsaid piece.

20. Clamping means comprising a support, a first clamp member slidablymounted on said support, a second clamp member pivotally mounted on saidfirst clamp member and means connected to said second clamp member andacting between said support and said second clamp member for forcingboth said members against a piece to be clamped.

21. Billet grinding apparatus comprising a table for carrying a billet,means for reciprocating said table connected thereto, means for mountinga grinding wheel adjacent said billet, means for reciprocating saidmounting means crosswise of said table connected to said mounting meansand means for clamping said billet on said table comprising a firstclamp member slidable along a path extending toward and away from theend of said billet and engageable with the end of said billet, meansacting between said clamp member and said table and urging said clampmember away from said end of said billet, a second clamp memberpivotally mounted at one end on said first clamp member, said secondclamp member having a billet engaging portion at the opposite endthereof and operating means mounted on said table and connected tosaidsecond clamp member, said operating means being adapted to apply a forceto said second clamp member directed along a path which intersects thepath of said first clamp member at an acute angle.

22. Billet grinding apparatus comprising a table for carrying a billet,means for reciprocating said table connected thereto, means for mountinga grinding wheel adjacent said billet, means for reciprocating saidmounting means crosswise of said table connected to said mounting meansand means for clamping said billet on said table comprising a firstclamp member slidable along a path extending toward and away from theend of said billet and engageable with the end of said billet, springmeans acting between said clamp member and said table and urging saidclamp member away from said end of said billet, a second clamp memberpivotally mounted at one end on said first clamp member, said secondclamp member having a billet engaging roller at the opposite endthereof, and cylinder and piston means mounted on said table and havinga piston rod connected to said second clamp member intermediate the endsthereof, said cylinder and piston means being mounted with said pistonrod movable along a path which intersects the path of said first clampmember at an acute angle.

23. Billet grinding apparatus comprising a table for holding a billet tobe ground, means for reciprocating said table connected thereto, meansfor mounting a grinding wheel adjacent said billet, and means forcontrolling the movement of said reciprocating means comprising meansactuated by said reciprocating means at predetermined positions thereoffor reversing the direction of movement of said reciprocating means andtiming means connected to said reciprocating means, said timing meansoperating at predetermined times independently of the movement of saidreciprocating means and being adapted to reverse the direction ofmovement of said reciprocating means at said times.

24. Billet grinding apparatus comprising a table for holding a billet tobe ground, means for reciprocating said table connected thereto andcomprising fluid actuated cylinder and piston means, means for mountinga grinding wheel adjacent said billet, means for controlling the supplyof fluid to said cylinder and piston means,

means connected to said controlling means and actuated by saidreciprocating means for reversing the direction of movement of saidreciprocating means at predetermined positions of said table and timingmeans connected to said controlling means for reversing the direction ofmovement of said reciprocating means, said timing means comprising meansoperating at predetermined times independently of the movement of saidreciprocating means for actuating said controlling means at said times.

References Cited in the file of this patent UNITED STATES PATENTS1,871,992 Heuze Aug. 16, 1932 2,021,066 Huxford et a1 Nov. 12, 19352,129,049 Doran Sept. 6, 1938 2,160,378 Balsiger May 30, 1939 2,176,486Bruestle Oct. 17, 1939 2,296,064 Silven Sept. 15, 1942 2,308,842 WilsonJan. 19, 1943 2,308,843 Wilson Jan. 19, 1943 2,334,023 Mulholland Nov.9, 1943 2,403,341 Carlson July 2, 1946 2,436,466 Wilson Feb. 24, 19482,442,042 Hamilton May 25, 1948 2,489,453 Fouquet Nov. 29, 19492,578,531 Flanders et al. Dec. 11, 1951 2,627,210 Kear Feb. 3, 1953FOREIGN PATENTS 221,029 Great Britain Sept. 4, 1924

